Electric fitting



ELECTRIC FITTING Filed Feb. 8, 1927 2 Sheets-Sheet 1 IN VEN TOR A TTORNEYS April 1930. G. w. GOODRIDGE 7 1,754,999

ELECTRIC FITTING Filed Feb. 8, 1927 2 Sheets-Sheet 2 IN VEN TOR ii aadlz'aye,

A TTORNE Y8 Patented 15, 1930 v UNITED s'm'rrs PATENT OFFICE GILBERT W. GOODBIDGE, OF FAIRFIELD, CONNECTICUT, ASSIGNOR TO THE BRYANT ELECTRIC COMPANY, OF BRIDGEPORT, CONNECTICUT, A CORPORATION OF CON- NECTICUT ELECTRIC FITTING Application filed February a, 1927. Serial m5. 166,702.

My invention relates to electric fittin s and particularly to electric lamp sockets, alt ough certain features of my invention may be readily embodied in fittings of various types.

Among the objects of my inventionmay be mentioned (1) to provide a fitting having a split insulating body which houses the switch mechanism, the parts being assembled thereon and held in position without the use of screws, bolts or the like; (2) to provide an improved switch mechanism of the ratchet type; (3) to simplify the mounting and attachment of wire terminal contacts; (4) to improve various details of structure hereinafter described or shown in the accompanying drawings, in which Fig. 1 is a broken side elevation of a pull socket in which my invention is embodied in one form;

Fig. 2 is a section on the line 2-2, Fig. 1;

Figs. 3' and 4 are partial sections on the lines 3-3, 4-4, respectively, of Fig. 2;

Fig. 5 is a section on the line 5-5, Fig. 2,

I but with the ratchet elements omitted;

Fi 6 is a section on the line 6-6, Fig. 2, but s owing the tensioningkeyin operating position;

Figs. 7 to 14 inclusive are perspective views of various elements of the contact-detached;

Fig. 15 is a perspective of the ratchet spring adjustment key; and

Fig. 16 is a partial section through a key socket embodying my invention.

It must be understood that the utility of the switch mechanism shown, is not limited to an electric lamp socket, and further that my invention, inso far as it relates to the assembly of metal parts on the split insulating body, may be utilized with switch mechanisms of various construction. It will fur- .ther beunderstood that upon the adaptation of my invention to fittings of other-types than that illustrated, appropriate modifications of construction will necessarily be-made. Consequently the socket structures shown in the accompanying drawings, will be recognized as merely appropriate embodiments of the features which constitute my invention.

Referring to the drawings, I have shown in Figs. 1 and 2 the conventional cap 17 and ration and relative rotation.

Supported Within the casing by the shoulder 20 thereof is the insulating ody of the socket. This insulating body is split, preferably diametrally on the longitudinal axis of the socket, forming blocks forming blocks 21 and 22 respectively recessed on their adjacent faces to afford a switch chamber 23.

At the lamp-receiving end of the body the blocks 21 and 22 are extended to form a boss 24 of reduced diameter exteriorly threaded at 25 to cooperate with the threads 26of the screw shell contact 27 of the socket. A beveled area 28 extends between the boss 24 and the main portion of the insulating body. The screw shell 27 departs from standard construction by having its base end offset outwardly at 29 and continued by an annular flange 30, the' margin of which is flared Cor coned to the bevel 28 of the socket body.

Consequently when the screw shell 27 is turned down on the threads 25 of boss 24, it not only unites the blocks 2122 by its engagement with the threaded boss thereof, but firmly clamps the blocks together throughout their area by reason of the compression effort exerted by cone flange 30 on the coned area 28 of the blocks. The clanipingaction is, in effect, like that of a cone clutch. Moreover, the extended surfaces of these cone areas establish a frictional engagement between the parts which effectually prevents the screw shell from backing off under the drag of a lamp base when unscrewed from the socket.

Inasmuch as no supplemental means are used to secure the blocks together, it is only necessary to assemble in appropriate relation thereto, the various elements of the structure, all being held in assembled position solely by the screw shell engagement with the threaded boss 24 and the thrust of the flange 30 against the cone shoulder 28 of the body when the shell is screwed home. The present invention thus affords an economy, not only from the standpoint of material, but

also from the standpoint of assembly expense.

The screw shell 27 is electrically connected to the wire terminal strap 31, which is appropriately shaped to lie in a recess 32 formed in the side wall of the block 22, and is clamped in position by the pressure of the flange 30 thereupon.

The other wire terminal 33 (see Fig. 5) comprises a sheet metal strip which, at its binding screw end, lies in a recess 34 formed in the adjacent side margins of the blocks 21, 22. Its shank is offset and extends from recess 34 through angular channel35 into the contact well 36 formed in the block 22. \Vhen the blocks 21 and 22 are juxtaposed they engage both margins of the combined wire terminal and switch contact strap 33, and hold the latter against escape, with the switch contact end 37 thereof located against one wall of the contact well 36.

Against the opposite wall of this well is arranged the switch contact end 38 of the center contact 39 for the socket, the two contacts being integral and being respectively offset from the intermediate portion 40 of the strap which lies in the channel 41 and 15 engaged and held in position by the uxtaposed buttons when the latter are assembled.

Within the switch well 36 is arranged the S-shaped spring switch bar 42 which alternately bridges the contacts 37 and 38 and breaks connection therewith. The well 36 is appropriately shaped to afford stop shoulders 43 which are engaged by the ends of the switch bar 42 and thus prevent reverse rotation of the latter.

To intermittently rotate the switch bar 42 I provide an operating spindle 44 and appropriate ratchet actuating devices mounted thereon. The spindle, which is formed from insulating material, is diametrally split at 45, at the end thereof which enters the switch well 36, and straddles the web of the switch bar, thus engaging the latter for rotation therewith. This split end of the spindle is extended beyond the switch bar, into the hearing recess 46 at the bottom of the well 36 and is journalled therein. Adjacent its split end, the spindle has integral therewith an annular flange 47, the face of which, remote from the switch bar 42, is provided with ratchet teeth 48. Adjacent the latter and freely mounted on the spindle is the driving disc 49, also of insulating material, appropriately apertured at to receive the several ratchet teeth 48 of the disc 47. The driving disc 49 is constantly stressed toward the ratchet flange 47 by the pressure of the coil spring 51which surrounds the spindle 44 and serves also as a torsion spring for returning the disc 49 to initial position after actuating displacement.

To enable the spring to perform its function as a return spring for the drive disc 49, one end 52 of the spring is extended laterally beyond the periphery of the disc 49 and is provided with an end loop 53, the portion 54 of which is engaged in the notch 55 in the periphery of the disc 49 adjacent the projecting stop lug 56. This loop 53 also serves as an anchorage for the end ball 58 of the pull chain 57. The usual chain rail on the driving disc is thus dispensed with and the chain is guided and confined in the annular channel 59 which surrounds the periphery of the drive disc 49. It will be noted that the diameter and thickness of the driving disc 49 are so proportioned with respect to the channel that the chain cannot escape from its position around the periphery of the driving plate when the parts are assembled. It will also be noted that the face of the stop lug 56 adjacent the anchor slot 55 isconcaved to engage the end ball 58 of the chain and confine it in position, at the same time wedging the portion 54 of the loop firmly into the anchor slot 55.

The opposite face of the stop lug 56 engages one face of the projection which enters the guide channel 59 and limits the angular return, of the drive discunder the torsional stress of the spring 51. A second lug 61 on the periphery of the drive disc engages the opposite face of the projection 60 and thus limits the angular displacement of the drive plate under the pull of the chain 57. It will be noted that the angular spacing of the lug 61 from the projection 60 is only slightly greater than 90, thus permitting only a quarter turn of the spindle on each successive ratchet drive thereof.

The opposite end of the spring 51 is pro vided with an offset lug 62 which engages one or the other of the offset lugs 63, 64 of the abutment plate 65. The latter is provided with a central collared aperture 66 to receive and form a bearing for one end of the spindle 44. It is also provided with diametral notches 67 and 68 to receive the lugs 69 and 70 of the adjusting key 71. In normal position the abutment plate rests in a rectangular recess 72 formed in the bottom of the portion of the switch chamber located in the button 21, and is held in this recess by the expansion of the spring 51. To adjust thetorsion of the spring 51, the ke 71 is inserted through the hole 73 in the block 21 which leads to the seat 72. The lugs 69 and of the key being engaged in the notches 67 and 68 of the abutment plate 65, the latter is displaced out of its seat by the thrust of the shoulders 74 of the key against the outer face of the plate 65, the spindle 44 being accommodated in the central recess 75 in the key end. The plate 65 being thus unseated may now be rotated by turning the key in either direction to increase or decrease the torsional stress on the spring 51 (see Fig. 6).

The exit of the pull chain 57 from the switch chamber is preferably guided by the chain bell 76, the inner end of which is prowith the exception of the pull chain, coil.

spring and binding screws, are formed from sheet metal, which may be readily formed to shape in appropriate dies'or bending apparutus. The driving disc 49 may be struck from sheet insulating material. Thespindle and ratchet disc 47 may be readily molded in one piece. On assembly, all of the parts,'with the exception of the screw shell contact'27, are merely -fitted into their appropriate recesses in one ofthe insulating body blocks,

the other block juxtaposed in register, and

the ensemble united and all parts held in position b the simple expedient of turning the screw s ell 27 firmly down upon the threaded boss 24: of the split body. N0 rivets, securing screws or bolts are required at any point.

. As above stated, my invention, so far as it concerns the general socket structure, is not confined to a ratchet operated switch. Thus it will be obvious from Fig. 5 that the switch bar 42 might readily be actuated by a keyoperated spindle. Or, as illustrated in Fig. 16, the switchcontacts may be modified to the form indicated at 76 and 7 7 for cooperation with the well known type of switch block 78 on spindle 79, the latter being rotated by thumb key 80.

Other modifications will readily occur to those dealing with the problem, as well as various alterations in details of construction which do not depart from the thoughts which underlie what I claim as my invention.

I claim 1. An electric fitting comprising a longitudinally split body having a threaded boss at one end, and a screw shell contact screw-- mg on said boss and having a wedging engagement with the split body beyond said boss to hold the parts firmly united.

2. An electric fitting comprising a longitudinally split body having a threaded boss at one end, a switch mechanism arranged between the body blocks, and a screw shell contact screwing on said boss and having a wedging engagement with the body blocks be yond said boss to hold said blocks firmly united, and to maintain the switch contacts in position therebetween.

3. An electric fitting comprising a longitudinally split body having a threaded boss at one end, the adjacent faces of said blocks,

being recessed to form a switch chamber with lateral channels extending therefrom, switch contacts arranged within the switch chamber and extending through said lateral channels to the outer face of said body, in combination with a screw' shell contact screwing in said boss and having a wedging engagement with the body blocks beyond said boss to hold the blocks united to maintain said contacts in position.

4. An electric fitting comprising a longitudinally split body having a threaded boss at one end, the adjacent faces of said blocks being recessed to form a switch chamber with lateral channels extendingtherefrom, switch contacts arranged within the switch chamber and extending through said lateral channels to the outer face of said body, in combination with a screw shell contact screwing in said boss and having a wedging engagement with the body blocks beyond sa1d boss to hold the blocks united to maintain said contacts in position, together with a switch spindle substantially normal to the plane of cleavage of said blocks, a switch member carried by said spindle serving to make and break circuit with said contacts on rotation of the spindle.

5. An electric fitting comprising a longitudinally split body having a threaded boss at one end, the adjacent faces of said blocks being recessed in register to afford a switch chamber with lateral channels extending therefrom to the exterior of the body, a switch contact arranged within said chamber and extending through one of said channels to the side of the body to afiord an exposed wire therebetween, together with a screw shell contact screwing on said boss and having a wedging engagement with the body blocks beyond said boss to hold the parts firmly united. v

6/ An electric fitting comprising a longitudinally split body havin at one end a threaded boss of reduced iameter and a beveled area extending between'said boss and the body blocks, in combination with a screw shell adapted to screw upon said threaded boss and having afiange flared to cooperate with the beveled area of the bolcks and exert a clamping efiort thereon to hold the blocks firmly united.

7. An electric fitting comprising a longitudinally split body having a threaded boss of reduced diameter at one end, and a beveled shoulder extending between said boss and the body, a wire terminal plate let into the outer face of said body and having a portion which extends into said beveled area, in combination with" a screw shell contact screwing on said boss, said screw shell having at its engaging end a flange flared to said beveled area of the body to bear thereon and on the wire terminal plate to establish contact between the screw shell and the latter, and to exert a wedging action upon the body blocks to hold the latter firmly united.

8. In an electric fitting, an insulating body recessed to afford a switch chamber with a peripheral guide channel for a flexible operating element, in combination with a switch mechanism arranged within said chamber and comprising a spindle of insulating material having rigid therewith a disc of insulating material with ratchet teeth upstanding from one face thereof, a second disc of insulating material perforated in register with said ratchet teeth and adapted to receive and afford a driving engagement with the latter, together with a flexible operating member opelratively connected to and riding on the periphery of said driving plate, the walls of the channel guiding the flexible member with respect to the driving disc.

9. An electric fitting comprising an insulating body and a ratchet operated switch mechanism mounted therein, said mechanism comprising a switch bar, a spindle of insulating material diametrally split at one end to afford a driving engagement with the switch bar, said spindle having rigid therewith a disc of insulating material adjacent said split end, the face of said disc opposed/to said split end having ratchet teeth integral therewith and projecting therefrom for cooperation with an associateddriving member.

10. An electric fitting comprising an insulating body and a switch mechanismmounted therein, said mechanism comprising a spindle of 1nsulat1ng materlal and having rigld therewith a. disc of insulating maengagement by the spring end and being marginally notched for engagement by the teeth of an adjusting key, said insulating body being recessed to afford a shallow noncircular seat for said abutment plate, from which the latter may be displaced for rotation to adjust the stress of said spring.

13. An electric fitting comprising an insulating body and a switch mechanism mounted therein, said mechanism comprising a ratchet drive plate having a notch in its peripheral surface, a flexible pull member on said peripheral surface, a coil returnspring having one end offset for engagement with said notch and also affording an anchorage for the end of said flexible pull member.

In testimony whereof I have signed my name to this specification.

GILBERT W. GOODRIDGE.

terial provided on one face with ratchet teeth integral therewith, together with a cooperating drive plate of insulating material apertured in register with said ratchet teeth, and adapted to receive the latter to afford a driving engagement.

11. An electric fitting comprising an insulating body and a switch mechanism mounted therein, said mechanism compris ing a ratchet drive plate, a coil return spring adapted to co-operate with said drive plate to turn the latter to normal position, a fiexible pull member adapted to ride the periphery of the drive plate and to turn the said plate from normal position, said insulating body being shaped to afford a guide channel for said flexible ull member around the periphery of said drive plate.

12. An electric fitting comprising an insulating body recessed to afford a switch chamber, a ratchet operated switch mechanism arranged therein, said mechanism comprising a ratchet drive plate, a coil return spring, one end of which operatively engages said ratchet drive plate, an abutment member engaged by'the opposite end of said spring,

said abutment member comprising a sheetmetal piece of non-circular shape having a lug offset toward said ratchet drive plate for 

